A number of previous studies have documented that exposure to cholinesterase-inhibiting pesticides such as organophosphates (OPS) and carbamates constitutes a major health problem. A number of studies have also examined the impact of OP poisoning and the impact of routine long-term exposure to pesticides in adults. The impact of long-term exposure to pesticides on children has been relatively unexplored. One objective of the proposed research is to examine the impact of chronic routine exposure to pesticides on cognitive and motor performance in children between 7 and 12 years of age. The specific areas tested will be memory performance, executive function performance, motor performance, and performance on school-related achievement tests. The proposed research will also measure concentrations of the pesticides (2, 4- dichlorophenoxyacetic acid) lindane and chloropyifos in the blood and urine in a sample of children between 7 and 12 years of age. These three pesticides are heavily applied in farming areas of the northeast quadrant of North Dakota where the participants will be recruited. In addition, blood will be assessed for concentrations of trace minerals and parents will complete a dietary intake questionnaire and the core food security module.